Try it
How to use this calculator
If you know the amount in ml, choose Amount (ml). If you have decided how many cups to brew, choose Cups and also enter the size of one cup; the two are multiplied to get the total. Then pick 1:15, 1:16 or 1:17 and the weight of coffee (g) and the amount of water (ml) appear right away. If this is your first time, start with the middle value, 1:16.
Where does the ratio come from
The range 1:15 to 1:17 is a common starting range for home hand drip. It is a rule of thumb that people often use, not an official standard, so treat it as a first reference point rather than the answer. If the cup tastes strong, add a little water next time; if it tastes weak, use a little less. The range and the order for adjusting it are explained in our blog post on the hand drip ratio.
Why weigh with a scale
Even the same spoon holds a different amount depending on the grind size and the roast of the beans, so we suggest weighing in grams rather than counting spoons. The coffee value here is in grams too, so one kitchen scale is all you need. You can weigh water on the same scale, counting 1 ml as 1 g.
How it is calculated
- Coffee (g) = Water (ml) / Ratio
- Water (ml) = Amount to drink (ml)
- Total amount (ml) = Cups x Per cup (ml)
The ratio says how many times the weight of the coffee the water weighs. For example, 1:16 means 16 g of water for every 1 g of coffee, so for 300 ml of water you divide 300 by 16 and get 18.8 g of coffee. Coffee is shown to one decimal place and water as a whole number.
Example table by amount
The values below were computed by the same function when the site was built. Columns are ratios, rows are amounts to drink, and each cell is the weight of coffee needed in grams.
| Amount (water) | 1:15 Coffee (g) | 1:16 Coffee (g) | 1:17 Coffee (g) |
|---|---|---|---|
| 150 ml | 10 | 9.4 | 8.8 |
| 200 ml | 13.3 | 12.5 | 11.8 |
| 300 ml | 20 | 18.8 | 17.6 |
| 400 ml | 26.7 | 25 | 23.5 |
| 500 ml | 33.3 | 31.3 | 29.4 |
The amount of water equals the amount to drink.
What about water temperature and time
This calculator only works out the amounts of coffee and water and does not set a water temperature. Even at the same ratio, longer contact or a finer grind can make the cup stronger and more bitter, so fix the ratio first and then change the grind and the time a little at a time.
Frequently asked questions
Which should I pick: 1:15, 1:16 or 1:17?
Brew your first cup at 1:16, the middle value. If it tastes strong, move toward 1:17 with more water; if it tastes weak, move toward 1:15. This range is a rule of thumb, not an official standard.
Why is the coffee in my cup less than the water amount shown?
The calculator only multiplies, so the water absorbed by the coffee is not counted. The cup is therefore a little smaller than the water you pour. To land exactly on a target, note how much you got once and pour a little more water next time.
Can I measure the coffee with a spoon?
We do not recommend it. One spoonful weighs differently depending on the bean type and the grind. For the first few brews, weigh it on a scale, find the weight that suits your taste, and write it down.
Compare it with a cup made at Soruru
Soruru is a cafe that introduces hand drip coffee, brewed slowly one drop at a time from beans roasted fresh each morning. To compare with what you brew at home, read the coffee story on our menu page.